This invention relates to valve structures and more particularly to a diverter valve that incorporates an improved closure mechanism and anti-knocking mechanism.
Diverter valves are commonly used in water tap or faucet assemblies to divert water between a spout and a hand spray. When the spray is operated, the diverter valve shuts off the flow of water to the spout. When the spray is shut off, the diverter valve automatically adjusts to allow water to flow from the spout again. Such systems are particularly used in domestic environments, as well as commercial establishments,
A common method of implementing this automatic diverter system is by means of a piston mechanism. The valve comprises a housing containing a valve member shaped to act as a piston. The valve member is movable from a first position, in which the outlet to the spout is open, to a second position, in which the outlet to the spout is closed off. The piston is responsive to a difference in pressure between the spray outlet and the inlet, so that when the spray is open, the piston moves to close off the spout. Additionally, such a valve may comprise both hot and cold water inlets, such that mixing of the hot and cold water occurs. For example, Moen (U.S. Pat. No. 2,949,933) describes a hot and cold water mixing valve, which can also automatically divert the mixed water from a principle outlet passage to an auxiliary outlet passage when a control valve on the auxiliary passage is opened.
However, a problem with existing diverter valves is that they only operate over a limited pressure range. At high pressures, leakage tends to occur. At low pressures, there is not enough force to close the seal on the spout properly, again resulting in leakage.
Another problem is the tendency for knocking to occur. Knocking is when a valve member is quickly moved from one position to the second position and rebounds back, thereby producing an audible hammering effect in the water line. It can be sufficiently loud as to make someone using the spray/spout system to believe that there is something seriously wrong with it. In U.S. Pat. No. 4,577,653 (Masco Corporation), a new design of valve is described, which is intended to reduce knocking of the valve member in the housing. This is achieved largely by prongs at the bottom of the upper housing part which bear on the conical mid-portion of the valve member. However, the design of Masco's valve is extremely complicated. The present invention aims both to improve substantially on the pressure range over which the valve will operate, and to reduce the amount of knocking which occurs, based on a design which is fairly straightforward and easy to construct.